This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This study evaluates the efficacy of a CRH1 receptor antagonist in reducing chronic diarrhea and self-injurious behavior (SIB) in captive housed rhesus macaques. Chronic diarrhea in the absence of identifiable pathogens and SIB are two of the most troublesome clinical conditions in rhesus monkeys housed in biomedical research facilities, for which current treatment methods are often ineffective. Chronic exposure to psychosocial stress plays a role in these conditions. Emerging data indicate that corticotropin releasing hormone (CRH) mediates stress-induced anxiety and depression, and that these emotional problems are corrected by treatment with specific CRH1 receptor antagonists. Furthermore, this treatment also attenuates stress-induced gut motility and the incidence of diarrhea. The purpose of this study is to determine whether treatment with a CRH1 receptor antagonist can ameliorate chronic diarrhea in the absence of enteric pathogens and/or reduce SIB in rhesus macaques. Data obtained from this study has the potential to greatly impact the clinical health of rhesus monkeys both at our center and at other biomedical research facilities, improving animal welfare and allowing for quality research. During the reporting period, we completed data collection in a small group of monkeys with chronic diarrhea. We are currently identifying additional animals for study assignment. Measures that improved the health of the colony will facilitate the diverse research program of the Center including AIDS vaccine development.